mcgraw hill wireless data demystified phần 7 docx

332 Part 3: Installing and Deploying Data Networks Scripting wrappers for file delivery specs Part of a total mobile and wireless infrastructure solution 1 Data Synchronization Options Data synchronization requirements for hand-helds generally fall into one of two categories. Basic data synchronization requirements are com- mon for relatively simple data access and collection applications that are usually new and replace paper-based systems. The basic data synchro- nization server acts as a communications server, managing the simulta- neous connection of many users and passing information between the device’s data store and a server database through a conduit. A variety of communications modes are supported. Thus, users may connect through desktop cradles, wireless data communications, dial-up, or direct net- work access. Basic synchronization capabilities include: Basic enterprise infrastructure platform features (see below) Integration with the standard device synchronization mechanism such as HotSync for Palm hand-helds Multiple communications modes Field-level change posting Full device refresh Refresh from an intermediate repository Support for standard IP Detailed logging and alerts Extensive administrative control and configurations Part of a total mobile and wireless data infrastructure solution 1 Basic synchronization servers typically have a documented API. The IT organization writes the conduit previously mentioned. This conduit is custom code written to the API of the synchronization server to define the data mappings, data sharing, and synchronization logic and sup- porting functionality. For straightforward applications, the conduit cod- ing effort is easily accomplished. With more complex requirements, it is more efficient to utilize an advanced data synchronization server than to try to write additional functionality and management tools into your conduit. Typical requirements that favor the robust functionality and rich management tools of an advanced data synchronization server include the following: Chapter 13: Deploying Mobile Wireless Data Networks Support for PC or laptop clients is also required Business processes evolve rapidly Connected users share enterprise data Information flows between mobile users Data refresh/realignment is required A complex data model is being synchronized Very large transaction volumes Processes run against the central database Mission-critical transactions are synchronized Robust administrative tools are required 1 Basic data collection applications, such as inventory, warehouse, ship- ping, inspections, and meter reading, often find basic synchronization solutions adequate to meet their requirements. When the preceding crite- ria are present, purchasing an advanced data synchronization engine will provide significant cost savings when compared with the cost of writing, supporting, and debugging a large amount of custom conduit code written to define sharing rules and provide the features mentioned next. If your needs require an advanced data synchronization solution, look for the fol- lowing features to be sure you are getting everything you’ll need: Basic enterprise infrastructure platform features (see below) Support for heterogeneous databases Store-and-forward architecture Fast synchronization sessions Rich administrative tools Change capture including triggers, ODBC, and logs Transaction support—serialization and rollback Flexible conflict management and resolution Support for multiple communications layers Full bidirectional synchronization with sharing logic Parameterized sharing rules Field-level synchronization, partitioning, and data mapping Performance tuning utilities Support for complex database schema Nonintrusive architecture to easily integrate 333 334 Part 3: Installing and Deploying Data Networks Sharing realignment and full client refresh capabilities An API for custom modifications SQL function trapping to preserve integrity Client-side error logging Part of a total mobile and wireless infrastructure solution 1 Building in all these features via custom coding to augment the basic data synchronization communication server can drain significant resources. However, these capabilities are vital in managing your mission-critical enterprise data. As a result, organizations should look to buy, rather than build, an advanced data synchronization engine. With basic PIM and e-mail synchronization, personalized file distribu- tion, and data synchronization set up, you’ll be providing users with most of the information they need to be productive, and you’ll be effortlessly gathering and consolidating data from the field. Next, let’s address some of the administrator’s needs. System Management and Inventory Synchronization of corporate data often requires that related applica- tions be deployed on the mobile devices. Management of application soft- ware and systems quickly also becomes a major requirement of a mobile infrastructure strategy. Application Management LAN-based approaches to system management of mobile devices are usually unworkable. Mobile users are intermittently connected through unreliable communications and require event-driven synchronization sessions. These factors introduce unique requirements. Support staff are unable to physically access the machine and must somehow keep track of overall inventory and the individual characteristics of each device. Thus, mobile and wireless data devices demand a different type of system management solution, one that complements existing systems, but meets the unique needs of the occasionally connected user. Key fea- tures of a mobile system management solution should include: Basic enterprise infrastructure platform features (see below) Self-upgrade support and healing Delivery logging Chapter 13: Deploying Mobile Wireless Data Networks Publish and subscribe model Software package wizard Device history tracking Software inventory Scripts that are able to access inventory data Scanner utility Byte-level file differencing Offline installation Versioning Part of a total mobile and wireless infrastructure solution 1 Utilizing software distribution capabilities makes the IT staff more efficient at managing the mobile devices, protects user productivity, low- ers costly support incidents, and prevents user downtime. Managing the Mobile Network A comprehensive mobile infrastructure solution is necessary to achieve consistent and efficient management of your mobile network. Reactive and fragmented support is not an option. Deployment of one integrated mobile computing suite, complete with common administrative and user interfaces, will provide a host of benefits. Demand Comprehensive and Fully Integrated Service Working with a single vendor means a single contract and a single source for support. Integrated administration reduces duplicated efforts, provides for a simple and efficient end-user interface, and reduces train- ing for IT staff by eliminating multiple tool sets. Cost savings are also realized through the elimination of application integration costs and reduced license, maintenance, and support expenses. You should look for a strong underlying platform in the solutions you consider. Must-have features include the following: Support for all major hand-held devices Integrated management Multiple connection modes 335 336 Part 3: Installing and Deploying Data Networks Remote server administration Administrative database Compression Scalable architecture Alerts and notifications Microsoft Management Console plug-in Directory services integration NT domain authentication Manage performance thresholds and load balancing Server-side process execution Encryption Open APIs Checkpoint restart in communications Standard Internet technologies Guaranteed delivery Logging and reporting Administrator-set scheduled connections Administrative Console The administrative console is the focal point for configuring and manag- ing your mobile and wireless data infrastructure. It should offer a robust administrative interface for maintaining the settings and rules that drive the behavior of server-based engines. Ideally, you can have one administrative console that manages all functions for all mobile devices you support. This console should allow system managers to: Define the user base Define activities (file, software, e-mail, and data distributions) Subscribe users to activities Prioritize the order of activity execution Review extensive system logs Review mobile device inventory Set alerts and notifications Troubleshoot and address problems 1 Chapter 13: Deploying Mobile Wireless Data Networks The administrative interface will allow you to interact with the mobile wireless data network, provision new users, model changing business processes, track down problems, monitor the aggregate device inventory for planning, and complete all the other day-to-day tasks involved in supporting mobile users. It’s important to have one central console, instead of learning a variety of administrative interfaces and duplicating tasks such as assigning a new user to a profile. Ideally, you can manage the entire mobile network from one GUI. Communications Options A variety of communications options are available for connecting hand- held devices to company servers for synchronization. It is very likely, and often advisable, for your organization to employ a mix of the following: Cradle to PC synchronization, which requires some sort of staging on PC Cradle through PC to network synchronization Network cradle synchronization Network dial-up (wired and wireless data) Wireless data direct to server over Internet synchronization (also wired) 1 The specific options available will vary for different hand-helds, and for different communications/networking providers. A full review of these is beyond the scope of this chapter. The important thing to keep in mind is that the networking and connection options must serve the user. And mobile users need options to stay connected when they are out of range of a wireless data connection, or have only a low-bandwidth dial-up connection available from a hotel, for instance. So, your hand-held infrastructure solution, including the synchro- nization and management tools, will need to support a range of commu- nications protocols and transport mechanisms. The vendor should be committed to providing a total solution with the flexibility you need today—and tomorrow. Security Concerns IT is ultimately responsible for the integrity, confidentiality, and avail- ability of the enterprise system. A comprehensive infrastructure plan will include the early integration of security solutions. The most basic 337 338 Part 3: Installing and Deploying Data Networks and inherent security risk posed by a mobile device is that it is not bolted down. It walks out your doors every afternoon. It is left in your salesper- son’s car. It is carried on planes, trains, and automobiles, and left in hotel rooms around the world. And it contains information critical to your business. Security on the New Frontier Mobile enterprise security is founded in policy and supported by cutting- edge technology. A comprehensive mobile enterprise security solution will include: Broad platform support. From enterprise and e-commerce 3 servers, to desktops and Java, all the way down to PDAs, smart phones, and Internet appliances. Standards compliance. Support for all the current and de facto standards, and complete interoperability with past, present, and planned installations. Network independence. The ability to build a solution for Internet, intranet, wireless data, and even nonstandard networks. Mobile, hand-held, and embedded specialization. Toolkits optimized to provide full-strength security that is small, fast, and efficient even in the smallest devices. Client authentication. Provide the highest form of security on any platform, even hand-helds—a must-have feature for enterprise data access and financial transactions. 1 Conclusion In midst of challenges to launching an enterprise hand-held wireless data deployment, how are companies realizing success? The answer is some- thing of an enterprise epiphany: whenever CEOs and CFOs say to them- selves, “We are going to have a mobile wireless data network and we are not afraid to support it.” The moment strikes when decision makers real- ize that to become more effective, more efficient, and more competitive, they don’t have to develop big pieces of software. They discover that mobility is less about moving people and more about moving information. They discover that smaller pieces of software can be rapidly deployed to hand-helds which link back to their server and effectively push critical data out into the field where users interact with the market. Chapter 13: Deploying Mobile Wireless Data Networks Now, the person you could have given a $4000 laptop is doing the same effective work with a $149 Palm OS hand-held because you have harnessed the information technology power of your existing back-end infrastructure. It’s a small price to pay when you stand to gain a full return on your investment in as little as 2 months. And, having deployed a flexible mobile and wireless data infrastructure platform, no matter what new mobile device is coming, your wireless data network is pre- pared to meet it head on. References 1. The Handheld Applications Guidebook: Getting Started Deploying and Supporting Enterprise Applications on Handheld PDAs, Synchro- logic, Inc., 200 North Point Center East, Suite 600, Alpharetta, GA 30022, 2002. 2. John R. Vacca, i-mode Crash Course, McGraw-Hill, 2001. 3. John R. Vacca, Electronic Commerce, 3d ed., Charles River Media, 2001. 339 This page intentionally left blank. Implementing Terrestrial Fixed Wireless Data Networks 14 CHAPTER 14 Copyright 2003 by The McGraw-Hill Companies, Inc. Click Here for Terms of Use. [...]... Prentice Hall, 2001 7 John R Vacca, Wireless Broadband Networks Handbook, McGraw- Hill, 2001 8 John R Vacca, Satellite Encryption, Academic Press, 1999 15 Implementing CHAPTER Wireless Data and Mobile Applications Copyright 2003 by The McGraw- Hill Companies, Inc Click Here for Terms of Use 356 Part 3: Installing and Deploying Data Networks The implementation of mobile wireless data applications 2... Often your server database may have a different schema from your client device’s database—especially on your hand-held clients Your synchronization solution should support mapping to eliminate dissemination of unneeded columns or tables and wireless data distribution to a database with schema differences Rule-Based Wireless Data Sharing Allocating wireless data among users streamlines data flows and minimizes... event that one component of a wireless data transaction is conflicting, column-level data rejection ensures that only the most granular conflicts are discarded Operation rejection In the event of wireless data conflict surpassing acceptability thresholds, operations are rejected.1 Wireless Data Distribution Rules Administrators should be able to graphically partition wireless data and allocate information... platform Automated Data Type Conversion In addition to supporting multiple client and server databases, your synchronization solution should include the ability to convert data types This feature enables the synchronization engine to modify wireless data to fit the server or client database requirements This feature is vital in organizations employing multiple database types Typical wireless data type conversions... changes to database schema Your wireless data synchronization solution should feature a variety of change capture mechanisms including: Triggers ODBC drivers Transaction logs1 Triggers Using trigger capture allows the synchronization solution to capture changes from any wireless data and mobile application that makes modifications to the database These possible sources include the client wireless data and... other data sources, and LAN users connecting to the database Triggers allow 362 Part 3: Installing and Deploying Data Networks the application developers complete freedom in choosing how they access the database, capturing changes from native libraries, ODBC, ADO, etc ODBC Drivers All databases essentially provide an ODBC interface Wireless data and mobile application developers that want to provide database-independent... support a variety of database vendors by requiring the integrator to supply change capture and scripts for the target platform Database Schema Protection Wireless data synchronization should be nonintrusive to existing enterprise applications and databases Existing tables and the synchronization mechanism should not affect the wireless data and mobile applications’ access to the database Light-Client...342 Part 3: Installing and Deploying Data Networks Terrestrial wireless data communication may be mobile4 or fixed The first and second generations of wireless data technology emphasized mobility and lower frequencies, since they sought to provide only basic wireless data telephony and low-speed data communications The third generation saw mobile technologies operate... 100-Mbps ranges for wireless data LANs (such as the Breeze Net Pro.11 product line) can range from 1000 m (3280 ft) in open areas to 60 to 200 m (200 to 650 ft) inside buildings Wireless Local-Area Networks WLANs use all -wireless data Ethernet and specialized hybrid technologies An all -wireless data Ethernet LAN replaces cabling 6 among computers in 348 Part 3: Installing and Deploying Data Networks a... centralized data centers, remote administration allows administrators to observe server activity from their workstations Log Data Stored in Server Database In addition to controlling the synchronization process, a sophisticated wireless data synchronization solution lets administrators track a variety of user behaviors and captures this in a server database Storing log data in a server database enables . (Motorola transportation data (nationwide), DataTAC) support, in-building 9.6 kbps wireless (limited) BellSouth Two-way paging, dispatch, 900 MHz (12.5 kHz) 4.8 kbps wireless data database (Mobiltex) AMPS. second generations of wireless data technology emphasized mobility and lower frequencies, since they sought to provide only basic wireless data telephony and low-speed data communications. The. Fixed Wireless Data Technologies Table 14-2 lists several terrestrial fixed wireless data technologies that are available. 1 For each technology, the typical frequency and channel bandwidth, data